i just got these head for $150, i was told they had a valve job but i dont know if it does at all. casting # 409 147, 64cc chamber. so i think i did good.

 

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there are the heads.

 

Looks nice. 150 for a complete valve job seems pretty cheap. I thought most shops doing a valve job would also install new valve guide seals, pivots, rocker arms, springs and keepers.

 

7a heads are decent heads. Did you get them local or have to pay shipping on top of that? Do you need the springs, rockers, etc or did you get them too?


John

 

Just out of curosity they are 7a right? My straight #7s were 409 147s. Did you cc the chambers to get that 64cc volume?

 

i picked them up local, an i am going to send the heads to a head shop just to make sure the heads had work done to them, I would like to make them preform better an just to make sure so ill let the heads guy put on the springs for me as well .

 

I agree.


nope that is what the guy told me,an what was in the add. but im going to take them to a head shop to make sure.

 

IMO, valve train components have nothing to do with the valve job. Seals, springs, keepers, usually, but without knowing the cam specs, it is kinda hard to set spring pressures and check coil bind, especially for $150. Rockers are never included. I bet you find a WIDE single angle seat.

 

well looks like im cam shopping asap!

 

IMO the cam is one of the last parts to buy, after true compression ratio has been determined, then matched to the other components, gear, converter, use, etc.

 

well looks like im going to need help picking the right cam,all im doing to the engine is rebuilding the top end being intake heads exhaust manifold an the cam/kit,of course i will be upgrading some pieces as i go through it but thats the plan for this engine .

 

Jim's right, get the rest of the combo sorted out first, then get your cam, springs etc.

 

well just doped off the heads,was told to read my psi of my pistons to see if there dished an if so how bad of loss in compression i have.

 

what year 350 do you have?

 

79 its the one that came with my hurst olds

 

OK, I did not see where that was posted. So, you have 14 cc dished pistons that should sit down .020 in the hole. Use .028 head gaskets and mill the heads down to 64 and you will have 9 to 1 CR. Mill to 60 cc and you are at 9.5 to 1. Also, 79 350s have 1/2" head bolts and the older 350 heads are 7/16" so you will need them drilled to 17/32" No biggie.

 

ty bud i just picked up a compression tester to see what kind of psi i'm sitting on just to see if my hopes of getting 350 or so out of this engine would be possible.

 

You are mixing up static compression with cranking compression. Static compression ratio is a combination of bore, stroke, and volumes. Cranking compression is variable depending on many factors. You need to know the static Cr to properly build the engine combo.

 

im sorry i was told by the guy who is doing my heads that i would need to no the psi in the cylinders to know if 300-350 would be a possible,he told me that there needs to be at lest 100 psi or more.sorry i am new to making more horse power out of an engine

 

He needs to know the compression ratio. You can take a 10 to 1 engine and have 220 psi cranking or 120 psi cranking, depending on the cam.

 

How much have the heads been milled?
It usually takes at least .030"+ to get the chambers down to the mid 60cc range.
Get them measured to be sure what you have so you can calculate true compression ratio. Most of these will be between 68 and 72cc's before the first valve job.
Good luck.

 

@ warhead those heads may be bigger than 64 cc's as is usually the case . I had my 6 heads milled .024 and im at 66cc's

 

He knows that, he stated.
"Most of these will be between 68 and 72cc's before the first valve job."

 

Ah i did not see that .

 

Imo you should find another machinist.